CMMG 16.1in 5.7x28mm Replacement Barrel & BCG Kit

Description

This CMMG barrel and bolt carrier group kit provides the key components to build an AR-platform firearm in 5.7x28mm using CMMG’s patented Radial Delayed Blowback system. The design reduces BCG weight and moderates felt recoil compared with straight blowback systems while retaining features such as last-round bolt hold open. The components are intended for assembly into a Mk4/mil-spec AR15 upper and are compatible with a CMMG Mk57 lower or a Mil-Spec AR15 lower when used with CMMG 5.7 AR conversion magazines.

Key Specifications

• The chambering is 5.7 x 28 mm.
• The barrel measures 16.1 inches in overall length.
• The finish is Salt Bath Nitride for surface hardness and corrosion resistance.
• The exterior color is Black.
• The kit includes a barrel and bolt carrier group for AR-platform assembly.
• The product is intended to fit AR rifles and mil-spec uppers.
• The listed model designation is Replacement Barrel.
• The product type is categorized as a barrel and bolt carrier group kit.
• Compatibility notes indicate it works with Mk4/mil-spec AR15 uppers and CMMG Mk57 or Mk4 lowers when using the appropriate conversion magazines.

Manufactured to integrate with AR-platform builds, this CMMG kit delivers a practical path to a 5.7x28mm configuration using the company’s Radial Delayed Blowback system. The salt bath nitride finish and black exterior provide durable service and a low-maintenance surface. For builders and enthusiasts seeking a straightforward parts kit to assemble a mil-spec upper in 5.7x28mm, this offering supplies the core components and design features intended for reliable operation in the intended platform.